1. Field of the Invention
The present invention relates to a fuel cell system, more particularly, to a fuel cell system using a proton exchange membrane fuel cell (PEMFC).
2. Description of the Related Art
Fuel cells are classified into a polymer electrolyte fuel cell, a phosphoric-acid fuel cell, an alkaline fuel cell, a molten carbonate fuel cell, a solid oxide fuel cell and the like, depending on the kinds of electrolytes to be used. As to hydrogen to be supplied to the fuel cell, fuel such as natural gas, propane gas and methanol, are supplied after being converted into hydrogen rich gas by a reformer. Meanwhile, air supplied to the reformer for generating the hydrogen rich gas and to the fuel cell is directly supplied by use of a compressor and the like.
In such a fuel cell system, a pump for supplying to a cell unit with air and fuels is required. However, since the capacity of the pump used in the fuel system is large, the system may be enlarged. Furthermore, a motor in the pump may generate loud noises.
The present invention was made for solving the foregoing problems. An object of the present invention is to provide a fuel cell system with a small and simple structure without a pump for supplying fuel and/or air to the reformer and/or the cell unit.